This grant is to provide biostatistical collaboration for the Eastern Cooperative Oncology Group (ECOG). The collaborations include all appropriate activities associated with the planning, monitoring, data collection and analysis of data obtained from clinical trails carried out by the ECOG. Research and development is also conducted on statistical and computing software, methodology aimed at improving and making more efficient the planning, data management and analysis of clinical trials in cancer. During this next period, it is planned to: introduce a new ECOG mail system having bulletin board capabilities; distribute part of our developing ECOG microcomputer software to ECOG hospitals; continue the introduction of early stopping rules for ECOG trials when it is appropriate.